Field
Aspects of the present technique generally relate to an ophthalmologic apparatus, a tomographic image generation method, and a program.
Description of the Related Art
As an optical tomographic image obtaining apparatus which obtains a tomographic image of a living body and the like in a non-destructive manner or a non-invasive manner, a light interference tomographic image obtaining apparatus which is referred to as “optical coherent tomography (OCT)” has been used.
The OCT obtains a tomographic image using light. More specifically, a light beam reflected by a measurement target and a light beam emitted from a reference mirror interfere with each other, and data of wavelength dependency (more specifically, wavenumber dependency) of intensity of a light beam obtained by the interference is subjected to Fourier transform so that a tomographic image is obtained. Examples of such a light interference tomographic image obtaining apparatus include time domain OCT (TD-OCT) which obtains depth information of a measurement target by changing a position of a reference mirror, spectral domain optical coherence tomography (SD-OCT) utilizing a broadband light source, and swept source optical coherence tomography (SS-OCT) using a wavelength variable light source apparatus capable of changing an oscillation wavelength as a light source.
In the OCT, an image is generated utilizing light interference, and therefore, speckle noise is generated in a formed image. Japanese Patent Laid-Open No. 2011-95005 discloses a technique of obtaining tomographic images in positions intentionally shifted from a desired position on a fundus by a predetermined amount ΔY and performing averaging between the obtained tomographic image and a tomographic image in the desired position so that speckle noise is reduced. Furthermore, the predetermined amount ΔY may be set in accordance with an involuntary eye movement according to Japanese Patent Laid-Open No. 2011-95005.
However, in a case where an image of an eye having a large involuntary eye movement is to be captured, even if the amount ΔY of the intentional shift of the positions of the imaging of the tomographic images is zero, although the speckle noise is reduced when obtained tomographic images are averaged, a resultant tomographic image blurs. Specifically, reduction of the speckle noise included in the tomographic image and reduction of the blur of the tomographic image are not simultaneously attained due to the involuntary eye movement.